Tools developed in the TB/HIV Research Laboratory and recently improved at EpiVax have put the development of a novel, epitope-driven vaccine for HIV-1 within reach. During the course of preparatory research we prospectively identified novel HIV-1 CTL epitopes that are well conserved across HIV-1 clades, produced two DNA vaccine constructs containing these epitopes in a string-of-beads formation, and successfully transfected several constructs in target cells. During the course of this research project, we propose to screen additional CTL and Th epitopes, to refine and improve our vaccine constructs, to confirm the expression and recognition of the epitopes contained within our constructs, and to develop a series of HLA-supertype-homogenous plasmids to a state of readiness for a Phase I trial. Our specific aims for this project will be to: 1. Finalize and screen a list of carefully selected candidate HIV-1 class I and class II epitopes 2. Develop plasmids containing these epitopes that target antigen-presenting cells 3. Evaluate the expression of the epitopes by target cells and their recognition in vitro (in cell culture) and in vivo (in transgenic mice) 4. Depending on success of Aims 1-3, initiate pre-clinical safety and toxicity studies and file an IND application with the FDA The long term goal of this research project is to develop HLA-supermotif-homogenous plasmids containing highly conserved epitopes that will be combined in a DNA-plasmid HIV vaccine "cocktail." EpiVax, Inc. will define and select the epitopes in collaboration with the TB/HIV Research Lab; the Lab will screen the epitopes, develop plasmid constructs, and perform in vitro assays confirming the expression of the epitopes by cells transfected with the plasmid constructs. Dr. Weiner's laboratory will test these constructs in the transgenic mouse model (transgenic for A2 and DR 0101, initially). The final product of this joint effort will be a set of plasmids to be combined in an epitope-driven, oligonucleotide-based DNA cocktail vaccine for HIV.